Sewing-machine mechanism.



J. M. CHADWICK.

SEWING MACHINE MECHANISM.

APPLICATION FILED JAN. 17, l'9l6- Patented Apr. 3-, 1917.

lllIllmmumnmmmmmum JOHN M. CHADWIGK, 0F DAYTON, OHIO.

SEWING-MACHINE MECHANISM.

Specification of Letters Patent.

Patented Apr. 8, 1917.

Application filed January 17, 1916. Serial No. 72,413.

To all whom it may concern:

Be it known that I, JOHN M. CHADWIOK, a citizen of the United States, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Sewing-Ma chine Mechanisms; and I do declare the following to be a full, clear, and exact description .of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

This invention relates to new and useful improvements in sewing machines, and more specifically to the feeding means in the needle feed type of machines. ,An object of the invention is to provide a new and improved form of resilient and adjustable means for actuating the feeding devices. A further object of the invention is to provide a new and improved form of back stitch mechanism as will be hereinafter more fully described. To the above ends the new mechanism is simple in construction and efficient in operation and obviates well known defects.

Referring to the accompanying drawings which illustrate my improvements, Figure 1 is a front elevation of the head portion of the overhanging arm of a sewing machine with the cover plate removed and showing my improvements applied thereto; Fig. 2 is a similar view with some parts removed and others shown in section; Fig. 3 is a rear view of the cam-actuating means for the feeding mechanism; Fig. 4 is a section on the line 4-4 of Fig. 8; Fig. 5 is a section on the line 5-5 of Fig. 2; and Fig. 6 is a detail sectional view of the means for adjusting the resilient actuating means of the feeding mechanism.

Referring more particularly to the drawings, 1 represents the frame head in which vertically reciprocates a needle bar 2 provided with the usual needle 3. The needle 3 coeperates, in a well known manner, with a pressure foot 4 mounted on the lower end of a vertically movable rod 5 slidingly mounted in the frame head 1. The needle bar 2 is reciprocated vertically through the agency of a cross head 6 provided with a race 7 in which reciprocates an anti-friction pin 8 mounted on a cam disk 9 attached to the end of a driving shaft 9 which extends through the overhanging arm and is driven in the usual manner. slightly elevated during the feeding of the cloth, by a cam lever 10 pivoted at 11 and provided with a cam race 12, which receives an anti-friction pin 13 on the needle bar 2, and a slot 14 which receives an anti-friction pin 15 on the rod 5. The rod 5 is elevated against the action of a spring 16, the tension of which is adjusted by a thumb screw 17 and which is instrumental in pressing the pressure foot 4 against the cloth in a well. known manner. hen the needle 3 is in the cloth, the said cloth is fed by the following means Adapted to be placed in operative rela tion with the needle bar 2 is a lower antifriction pin 18 and an upper anti-friction pin 19 which pins are preferably made of fiber to eliminate noise. The pins 18 and 19 are mounted below and above the pivot 20 of the plate 21 upon which they are mounted. The plate 21 is provided with a finger piece 22 which extends out through the head 1 and by means of which the said pins 18 and 19 may be shifted in operative relation with the needle bar 2. The pins 18 and 19 are held in their shifted positions and are connected to their actuating means by any suitable means such as is shown in detail in Fig. 5 and which consists of a ball 22 controlled by a spring 23 mounted in a pocket 24 in said plate 21 and adapted to rest in either of two recesses 25 in a plate 26. The plate 26 which is the actuating plate for the pins 18 and 19 is pivoted on the pivot 20 and moves in unison with the plate 21 and pins 18 and 19. The said plate 26 is actuated by a lever 27 attached thereto at 28 and provided with an anti-friction roller 29 in operative relation with the periphery of the cam disk 9. The lever 27 is provided with a fulcrum 80 which is adjustable by means, not shown, to vary the length of the stitch. The lever 27 is held in operative relation with the cam 9 by a spring 31 connected to the lever and the plate 26. By the aid of the above described mechanism the needle bar is given a horizontal movement in addition to its vertical movement which enables the needle to feed with the cloth. The needle bar is moved in one direction by the cam 9 and in the opposite direction by a cylindrical spring 32 which is an important feature of the mechanism. The said spring 32 he pressure foot 4 is is attached at one of its ends 33 to a feed bar 3 1 and at its other end to a screw 35 mounted in the framehead 1. The said spring32 engages the threads of the screw as is shown in Fig. 6 and enables the tension of the spring to be, adjusted. By cnstructii'ig the resilient device for actuating the feed ng mechanism in this manner, the

, said resilient device is more efiicient in oporation in that it is more responsive and is not sub]ect to breakage. Also, as the said resilient device is adjustable, the tension thereof may be varied to suit the work to be performed on different weights of the cloth and whereby noise in the operation of the machine is eliminated. The bar 34 is providedwith a toe 37 adapted to engage the cloth and to assist the needle in feeding the same in a well known manner. The said bar at is elevated to free the cloth by the cam lever 10, the pivotll thereof being on said bar which is also a well known construction.

7, anti-friction pin 18 back and allowing the anti-friction pin 19 to engage the needle bar 2; This operation is accomplished by throwing the plate 21, by means of the finger piece 22, to a position to cause the pin 18 to'leave the needlebar and the pin 19 to 'refiopies of this patent may be obtained for main in contact with said needle bar. At this time the ball 22 engages the notch 25 in plate 26 and holds the plate 21 in the 'mechanism in the other direction, shiftable pins mounted on said actuator and in operative relation with said mechanism, and means for moving said actuator to bring one of said pins out of engagement with the needle bar and to thereby reverse the movement of said feeding mechanism.

In a device of the type specified, a horizontally movable needle feeding mechanism including a needle bar, resilient means for moving said mechanism in one direction, a shiftable pivotal plate, pins adapted to be placed in operative relation with said mechanism and mounted on said plate, and means for actuating said plate to bring one of said pins out of contact with the needle bar to reverse the motion of said feeding mechanism.

3. In a device of the type specified, a horizontally movable needle feeding mechanism including a needle bar, adjustable resilient means for moving said mechanism in one direction, a shiftable pivotal plate, pins adapted to be placed in operative relation with said needle bar and mounted on said plate below and above the pivot thereof, an actuating plate, means for connecting said plates, and means for moving said actuating plate.

In testimony whereof I aflix my signature.

JOHN M. CHADWIOK.

five cents each, by addressing the Commissioner of I'atents, Washington, D. G. 

